Numerous cartons with pouring structures are known, but none has been entirely satisfactory. For example, the spouts disclosed in U.S. Pat. Nos. 3,344,972 (to Robinson et al.), 4,054,240 (to LaPierre) and 4,194,677 (to Wysocki) require stripped out areas that may be difficult and expensive to form (LaPierre and Wysocki), overlying ears (Robinson et al.), and, in each case, large spout-forming bilateral ears or wing members. The latter requirement precludes the satisfactory application of the teachings of these patents to an optimum range of cartons, particularly those having a relatively small width or thickness.
U.S. Pat. Nos. 3,096,011 (to Davis) and 3,568,910 (to McConnell) disclose cartons with pouring spouts wherein the wings or spout sidewall-forming portions, respectively, are outside the carton where they may interfere with the reclosing of the spout (Davis). Additionally, the wings are quite small or narrow, thereby failing to form a complete spout having full sidewalls when the spout is opened fully.
U.S. Pat. No. 4,569,443 (to Roccaforte) solves some of the aforementioned problems, but still requires large spout side-forming wings, thereby precluding its useful application to an optimally wide range of cartons, particularly those for containing and dispensing powdered or granular food items which frequently need to be made available in smaller sizes. In such cartons, it has not been possible to provide a gluing area for the carton, full side-forming wings, and an area that defines the desired width of the spout itself within the constraints imposed by the carton.
Accordingly, there is a need for an integral pouring spout design that is simple, economical, durable, yet easy to open and close, that provides a spout with full sidewalls, and that can be used with a wide range of cartons.